Thursday, October 28, 2010

Ballard Team Has High Hopes for Deep-Water Robot

Brian Handwerkfor National Geographic News

July 16, 2003

Undersea explorer Robert Ballard has likened the ocean floor to a vast museum holding an unrivaled archaeological record of human history. This summer, as Ballard and a team of scientists embark on a 40-day expedtion to the Black Sea and Mediterranean, they will bring an exciting new tool for exploring this underwater realm.

Hercules, an innovative underwater remotely operated vehicle (ROV) equipped with mechanical arms, fingers, and a variety of tools, will enable Ballard and his team to conduct the first archaeological excavations of shipwrecks and archaeological sites in the deep sea.

The expedition team will revisit recently discovered archaeological sites in the Black Sea and Mediterranean. With Hercules in tow, the team hopes to conduct the first meaningful excavations of these sites.

The effort may yield more tantalizing clues about life in the Black Sea and Mediterranean regions during the age of ancient Greece. It could also turn up further evidence to support the Black Sea flood theory. The theory holds that following the last ice age, rising sea levels in the Mediterranean breached a natural dam that separated the two bodies of water, an event that resulted in a catastrophic flood that raised the Black Sea to its present levels.

Dynamic Duo

Ballard, a National Geographic Society Explorer-in-Residence and president of the Institute for Exploration (IFE) at Connecticut's Mystic Aquarium, and his team have relied on a pair of undersea vehicles, ARGUS and Little Hercules, on past expeditions.

The vehicles, designed to work in tandem, remain connected to the mother ship via an armor-plated fiber-optic cable laced with electrical wires. Pilots can maneuver the vehicles using remotely controlled thrusters.

Little Hercules' primary mission is to shoot high-definition video of underwater objects, artifacts, or shipwrecksallowing ship-based researchers to virtuallyand safelyexplore the ocean depths. The ROV's pilot uses four thrusters to maneuver Little Hercules freely on the 100-foot (30-meter) tether that connects it to ARGUS.

"All the vehicles IFE has had up to now are for survey and imaging," explained chief engineer Jim Newman. The president of Woods Hole Marine Systems Inc., in Woods Hole, Massachusetts, Newman spearheaded the efforts to build Hercules and numerous other ROVs used by Ballard.

"ARGUS and Little Herc feature camera systems that can go in and investigate sonar anomalies. With sonar, you just know that there's something weird there [on the ocean floor]. It could be a rock, a modern shipwreck, or something of real interest," he said. "The only way to determine that is to go in and get video. That's what Little Herc was built for."

But video is no longer enough. The time has come for the team to dig a little deeperliterally. Hercules, developed by IFE (with excavation tools developed by the Deep Submergence Laboratory at Woods Hole Oceanographic Institution), is specially designed for excavating and recovering artifacts from underwater archaeological sites and shipwrecks that rest at depths up to 3,000 meters (9,840 feet).

"You can learn a fair amount [with video]. But at some point you want to reach in there, start digging, and see what's there," Newman told National Geographic News. "This is an excavation vehicle, designed to perform the same kind of tasks that a land-based archaeologist does with his hands and tools."